Pteridinone derivatives are known from the prior art as active substances with an antiproliferative activity. WO 01/019825 and WO 03/020722 describe the use of pteridinone derivatives for the treatment of tumoral diseases.
Tumour cells wholly or partly elude regulation and control by the body and are characterised by uncontrolled growth. This is based on the one hand on the loss of control proteins, such as e.g. Rb, p16, p21 and p53 and also on the activation of so-called accelerators of the cell cycle, the cyclin-dependent kinases (CDK's).
In addition, the protein kinase Aurora B has been described as having an essential function during entry into mitosis. Aurora B phosphorylates histone H3 at Ser10 and thus initiates chromosome condensation (Hsu et al. 2000, Cell 102:279-91). A specific cell cycle arrest in the G2/M phase may however also be triggered e.g. by the inhibition of specific phosphatases such as e.g. Cdc25C (Russell and Nurse 1986, Cell 45:145-53). Yeasts with a defective Cdc25 gene arrest in the G2 phase, while overexpression of Cdc25 leads to premature entry into the mitosis phase (Russell and Nurse 1987, Cell 49:559-67). Moreover, an arrest in the G2/M phase may also be triggered by the inhibition of certain motor proteins, the so-called kinesins such as e.g. Eg5 (Mayer et al. 1999, Science 286:971-4), or by agents which stabilise or destabilise microtubules (e.g. colchicin, taxol, etoposide, vinblastin, vincristine) (Schiff and Horwitz 1980, Proc Natl Acad Sci USA 77:1561-5).
In addition to the cyclin-dependent and Aurora kinases the so-called polo-like kinases, a small family of serine/threonine kinases, play an important part in the regulation of the eukaryotic cell cycle. Hitherto, the polo-like kinases PLK-1, PLK-2, PLK-3 and PLK-4 have been described in the literature. PLK-1 in particular has been shown to play a central part in the regulation of the mitosis phase. PLK-1 is responsible for the maturation of the centrosomes, for the activation of phosphatase Cdc25C, and for the activation of the Anaphase Promoting Complex (Glover et al. 1998, Genes Dev. 12:3777-87; Qian et al. 2001, Mol Biol Cell. 12:1791-9). The injection of PLK-1 antibodies leads to a G2 arrest in untransformed cells, whereas tumour cells arrest in the mitosis phase (Lane and Nigg 1996, J Cell Biol. 135:1701-13). Overexpression of PLK-1 has been demonstrated for various types of tumour, such as non-small-cell lung cancer, plate epithelial carcinoma, breast and colorectal carcinoma (Wolf et al. 1997, Oncogene 14:543-549; Knecht et al. 1999, Cancer Res. 59:2794-2797; Wolf et al. 2000, Pathol. Res. Pract. 196:753-759; Takahashi et al. 2003, Cancer Sci. 94:148-52). Therefore, this category of proteins also constitutes an interesting approach to therapeutic intervention in proliferative diseases (Liu and Erikson 2003, Proc Natl Acad Sci USA 100:5789-5794).
The resistance of many types of tumours calls for the development of new pharmaceutical compositions for combating tumours. The aim of the present invention is to provide new compounds having an antiproliferative activity.